Stator supporting apparatus for reciprocating compressor

ABSTRACT

A stator ( 4 A) supporting apparatus for a reciprocating compressor includes a cap member ( 10 ), in which one end of an inner resonance spring ( 7 A) abuts to one end of the cap member ( 10 ) so that the vibration of the inner resonance spring ( 7 A) is transferred to the stator and the cap member ( 10 ) is isolated from the frame of the compressor so as to prevent the vibration of the inner resonance spring ( 7 A) from transferring to the frame ( 1 ) directly. Therefore, the vibration of the compressor is reduced by fixing the inner stator ( 4 A) strongly and transferring the vibration generated in the inner resonance spring ( 7 A) to the frame through the inner stator ( 4 A)

TECHNICAL FIELD

[0001] The present invention relates to a stator supporting apparatusfor a reciprocating compressor, and particularly, to a stator supportingapparatus for a reciprocating compressor which is capable of stronglyfixing an inner stator and attenuating vibration of the compressor.

BACKGROUND ART

[0002]FIG. 1 is a transverse, cross-sectional view of an examplaryconventional reciprocating compressor of the moving magnet type.Generally, a reciprocating compressor is constructed such that a pistonof the compressor is integrally combined with the armature (movingelement) of a reciprocating electric motor, instead of using a crankshaft.

[0003] As shown in FIGS. 1 and 2, a conventional reciprocatingcompressor includes a compressor unit (C) installed extendingtransversely inside a casing (V) filled at the bottom with lubricant,the compressor unit sucking refrigerant, compressing and discharging thesucked refrigerant, and a lubricant feeder, (O) is fixed outside thecompressor unit (C) for supplying lubricant to sliding parts of thecompressor unit (C).

[0004] The compressor unit (C) includes an annular frame 1, a cover 2fixedly installed at a one end of the frame 1, a cylinder 3 fixedtransversely in a central part of the frame 1, an inner stator 4A fixedin an inner part of the frame 1 supporting the cylinder 3 and an outerstator 4B fixed in an outer part of the frame 1 and spaced radiallyoutwardly from inner stator 4A by a certain gap; an armature 5 having apermanent magnet disposed in the gap between the inner and the outerstators 4A and 4B; a piston 6 fixed integrally on the armature 5 andsucking/compressing the refrigerant gas by performing sliding movementinside the cylinder 3; a pair of inner and outer resonance springs 7Aand 7B elastically assisting the continuous resonant movement of thearmature 5 in the gap between the inner and outer stators 4A and 4B; anda discharge valve assembly 8 installed on a front end of the cylinder 3.

[0005] Hereinafter, the left side of the Figures represents the frontside, and the right side of the Figures represents the rear side.

[0006] The inner stator 4A is formed by stacking a plurality of statorcore laminations 4 a side-by-side to form a cylindrical shape, and theinner surface of the inner stator 4A is coupled to the outer surface ofthe frame by being press fitted into the frame, and at the same time,the front end of the inner stator 4A abuts a stepped surface 1 a of theframe 1 so as to be supported thereby.

[0007] Reference numeral 9 designates a suction valve, and reference SPdesignates a suction pipe.

[0008] The above-described conventional reciprocating compressor isoperated as follows.

[0009] That is, when an alternating electric current is applied to thecoil carried by the outer stator 4B and an alternating magnetic field isgenerated between the inner and outer stators 4A and 4B, the armature 5undergoes linear reciprocating movement as the poles of the permanentmagnet thereof are alternatingly attracted and repulsed by the magneticfield in the gap, whereby the piston 6 coupled to the armature 5 alsoundergoes linear reciprocating motion inside the cylinder 3 so that apressure variance is repeatedly generated inside the cylinder 3.Accordingly, due to the pressure variance inside the cylinder 3, therefrigerant gas in the casing (V) is sucked into the cylinder throughthe gas flowing passage (F) in the piston 6, then compressed anddischarged through the discharge valve assembly 8. And this process isrepeated continually as the piston is shuttled in the cylinder.

[0010] At this time, as the armature 5 undergoes linear motion in thetransverse direction (in the drawing) due to the alternating magneticfields generated in the gap between the inner and outer stators 4A and4B, the inner and the outer resonance springs 7A and 7B supporting thearmature in both directions are compressed and stretched oppositely toeach other, causing the armature's reciprocation to be resonated.

[0011] However, in the conventional reciprocating compressor asdescribed above, only the front end of the inner stator is supported bythe frame, and the rear end of the inner stator is left free as it is,and therefore the inner stator can not be fixed strongly.

[0012] Also, a vibration is generated while the inner and the outerresonance springs resonate the movement of the armature, and thecompressor unit is vibrated thereby because the inner resonance springis abutted to the frame directly and supported thereat, and accordingly,vibration of the reciprocating compressor itself inside the casing isincreased.

DISCLOSURE OF THE INVENTION

[0013] Therefore, it is an object of the present invention to provide astator supporting apparatus for a reciprocating compressor which can fixthe inner stator strongly in order to solve the problems of theconventional art.

[0014] Also, it is another object of the present invention to provide astator supporting apparatus for a reciprocating compressor which canprevent of vibration of the compressor unit by the inner resonancespring when the inner and the outer resonance springs supporting thearmature are compressed and stretched.

[0015] To accomplish these objects of the present invention, there isprovided a reciprocating compressor comprising a frame supporting acylinder is installed elastically inside a casing; an inner stator andan outer stator constituting a stator of a motor are installed on theframe; an armature coupled integrally to a piston, which is insertedslidably into the cylinder, is disposed with a certain gap between theinner stator and the outer stator; and an inner resonance spring and anouter resonance spring supports the from front and rear sides of thearmature so that the armature undergoes linear resonant movement withthe piston; wherein a stator supporting apparatus for the reciprocatingcompressor in which one side end of the inner stator fixed on the frameis supported by a supporting member, and the other end part of thesupporting member is elastically supported by one end of the innerresonance spring, so that the vibration of the resonance spring istransferred to the frame through the inner stator is provided.

[0016] Also, to accomplish these objects of the present invention, thereis provided a stator supporting apparatus for a reciprocating compressorcomprising a frame elastically supported in a casing; a cylinder fixedlyinstalled on the frame; an inner stator and an outer stator fixedlyinstalled on the frame and constructing a stator in a motor; an armaturecoupled integrally with a piston inserted into the cylinder slidably,and disposed in air gap generated between the inner stator and the outerstator; an inner resonance spring and an outer resonance springsupported from both front/rear sides of the armature so that thearmature is able to undergo linear reciprocating movement with thepiston; and a supporting member in which an inner bent-up partsupporting one end of the inner resonance spring and an outer bent-uppart supporting one side of the inner stator are formed as a singlebody, whereby vibration of the inner/outer resonance springs is able tobe transferred to the frame through the inner stator when the motor isoperated.

BRIEF DESCRIPTION OF THE DRAWINGS

[0017]FIG. 1 is a transverse cross-sectional view showing a conventionalreciprocating compressor;

[0018]FIG. 2 is a cross-sectional view showing the fixing structure ofan inner stator in the conventional reciprocating compressor;

[0019]FIG. 3 is a transverse cross-sectional view showing an embodimentof a reciprocating compressor according to the present invention;

[0020]FIG. 4 is a cross-sectional view showing the fixing structure ofthe inner stator in the reciprocating compressor according to thepresent invention;

[0021]FIG. 5 is an exploded perspective view showing the fixingstructure of the inner stator in the reciprocating compressor accordingto the present invention; and

[0022]FIG. 6 is a cross-sectional view showing another embodiment of thefixing structure of the inner stator in the reciprocating compressoraccording to the present invention.

MODES FOR CARRYING OUT THE PREFERRED EMBODIMENTS

[0023] The stator supporting apparatus for a reciprocating compressoraccording to the present invention will be described with reference tothe accompanying drawings.

[0024] The same components as those of the conventional art aredesignated by the same reference numerals.

[0025] As shown in FIGS. 3 and 4, a reciprocating compressor, to which astator supporting apparatus according to the present invention isadapted, includes a casing (V) filled with lubricant at the bottom, andfitted with a suction pipe SP and an exhaust pipe(not shown); a frame 1of annular shape elastically supported within the casing (V); a cover 2fixed on an end surface of the frame 1; a cylinder 3 fixed in a centralpart of the frame 1 in the axial direction; an inner stator 4A fixed onthe inner part of the frame 1; an outer stator 4B fixed on an outer partof the frame 1 and spaced from the inner stator 4A by a certain radialgap; a armature 5 carrying a permanent magnet disposed in the gapbetween the inner stator 4A and the outer stator 4B and capable ofperforming linear reciprocating movement therein; a piston 6 fixedintegrally on the armature 5, inserted slidably into the cylinder, andcapable of linear reciprocating movement together with the armature 5;an inner resonance spring 7A and an outer resonance spring 7B supportingthe armature 5 from both sides of the armature 5 and inducting theresonant movement of the armature 5; and a cap member 10 disposedbetween the inner resonance spring 7A and the inner stator 4A, andelastically supporting the inner stator 4A.

[0026] The inner stator 4A is formed by stacking a plurality of statorcore laminations 4 a side-by-side to have a cylindrical shape, and thefront end of the inner stator 4A abuts against a step 1 a formed in theouter surface of the frame 1 so as to be fixed in the frontwarddirection, but at the other, rear end of the inner stator 4A, the capmember 10 being pressed elastically by the inner resonance spring 7A isabutted and supported.

[0027] Therefore, the cap member 10 itself performs as a spring basesupporting the inner resonance spring elastically.

[0028] The cap member 10, as shown in FIG. 5, is formed as a cylindrical‘cap’ having a central cylindrical bore 11 an inner bent-up part 12 atits one end, and a outer bent-up part 13 at its other end, and thecylinder 3 is extends through the bore 11 with a certain gap, so thatthe inner resonance spring 7A can be disposed between the inner surfaceof the bore 11 and the outer surface of the cylinder 3. In addition, thefront end of the inner resonance spring 7A is abutted against andsupported by inner bent-up part 12 of the cap member 10, and the rearend of the inner stator 4A is abutted by and supported by the outerbent-up part 13 of the cap member 10.

[0029] Also, in consideration of contacting of the cap member 10 withthe inner resonance spring 7A undergoing a vibration, it is desirablethat the front inner bent-up part 12 of the cap member 10 is spaced witha certain gap from the frame 1 so that the inner bent-up part 12 is notcontacted with the rear end 1 b of the frame 1.

[0030] Also, as another embodiment of the stator supporting apparatusfor a reciprocating compressor according to the present invention, thecap member 10′ may be constructed so as to contact the cylinder 3 andthe inner stator 4A at the same time, or the cap member 10′ may have apart which contacts the cylinder 3 and the inner stator 4A at the sametime. In FIG. 6, a construction where the cap member 10′ contacts theouter surface of the cylinder 3 and the rear end of the inner stator 4Ais shown. Accordingly, the fixing of the inner stator can be madestronger and more rigid.

[0031] In addition, the cap member 10′ is fabricated by a sheet metalforming process using a press machine.

[0032] The general operation of the reciprocating compressor having thestator supporting apparatus according to the present invention issimilar to that of the conventional art.

[0033] That is, when the armature 5 undergoes linear reciprocatingmovement after the electric current is applied to the coil carried bythe outer stator 4B, the piston coupled to the armature 5 performslinear reciprocating movement inside the cylinder, whereby the pressureinside the cylinder is differentiated, so the refrigerant gas inside thecasing (V) is sucked into the cylinder 3 through the gas flowing passage(F) in the piston 6, then compressed and discharged through thedischarge valve assembly 8.

[0034] At that time, if the armature 5 undergoes the linearreciprocating movement in the transverse axial direction in the gapbetween the inner and outer stators 4A and 4B, the inner resonancespring 7A among inner and outer resonance springs 7A and 7Bsupporting-the armature 5 from both sides presses against the cap member10, so that the cap member 10 pressed by the inner resonance springpushes against the rear end-of the inner stator 4A towards the frontwarddirection, whereby the inner stator 4A is abutted against the step 1 aof the frame more strongly.

[0035] That is, the front end of the inner stator 4A is fixed on thestep 1 a formed on the outer surface of the frame 1, and in that state,the rear end of the inner stator 4A is pushed in the frontward directionby the cap member 10 pressed by the inner resonance spring 7A, wherebythe inner stator can be fixed more strongly.

[0036] Also, the front end of the cap member 10 is not disposed directlyon the rear end 1 b of the frame 1, and therefore the vibration of theinner resonance spring 7A abutted to the cap member 10 is nottransferred directly to the frame 1, but is transferred to the frame 1through the inner stator 4A.

[0037] Because the inner stator 4A is constructed by stacking aplurality of stator core laminations 4 a, the vibration is compensatedto a certain level by the inner stator 4A and then transferred to theframe 1, whereby the vibration of the compressor can be reduced.

[0038] As so far described, according to the present invention, theinner stator for a reciprocating compressor comprises a cap memberadhering to the one side of the inner stator assembly corresponding tothe one end of the inner resonance spring, the inner resonance spring,which is adhered to the other side of the cap member, elasticallysupporting the inner stator and at the same time making the excitingforce-transfer to the inner stator, and the cap member is-disposed so asto be apart from the frame thereby direct transferring of the excitingforce generated in the inner resonance spring to the frame is prevented.Therefore, the inner stator can be fixed strongly, and the excitingforce generated during the compression or stretching process of theinner resonance spring is transferred to the frame through the innerstator, thereby the vibration of the compressor can be reduced.

INDUSTRIAL APPLICABILITY

[0039] The invention has applicability to reciprocating motors andcompressors as are employed widely in various industrial fieldsincluding refrigeration and air conditioning devices.

1. A reciprocating compressor comprising: a frame supporting a cylinderis installed elastically inside a casing; an inner stator and an outerstator constituting a stator of a motor are installed on the frame; anarmature coupled integrally to a piston, which is inserted slidably intothe cylinder, is disposed with a certain gap between the inner statorand the outer stator; and an inner resonance spring and an outerresonance spring supports the from front and rear sides of the armatureso that the armature undergoes linear resonant movement with the piston;wherein a stator supporting apparatus for the reciprocating compressorin which one side end of the inner stator fixed on the frame issupported by a supporting member, and the other end part of thesupporting member is elastically supported by one end of the innerresonance spring, so that the vibration of the resonance spring istransferred to the frame through the inner stator is provided.
 2. Astator supporting apparatus for a reciprocating compressor comprising: aframe elastically supported in a casing; a cylinder fixedly installed onthe frame; an inner stator and an outer stator fixedly installed on theframe and constructing a stator in a motor; an armature coupledintegrally with a piston inserted into the cylinder slidably, anddisposed in air gap generated between the inner stator and the outerstator; an inner resonance spring and an outer resonance springsupported from both front/rear sides of the armature so that thearmature is able to undergo linear reciprocating movement with thepiston; and a supporting member in which an inner bent-up partsupporting one end of the inner resonance spring and an outer bent-uppart supporting one side of the inner stator are formed as a singlebody, whereby vibration of the inner/outer resonance springs is able tobe transferred to the frame through the inner stator when the motor isoperated.
 3. The apparatus according to claim 2, wherein the supportingmember is a cap member constructed so that the supporting surfaces ofthe outer bent-up part supporting the inner stator and of the innerbent-up part supporting the inner resonance spring are located differentsurfaces with each other.
 4. The apparatus according to claim 3, whereinthe cap member is fabricated by a sheet metal forming process.
 5. Theapparatus according to claim 3, wherein the cap member is disposed apartfrom the frame, whereby the vibration of the inner resonance spring isnot directly transferred to the frame.
 6. The apparatus according toclaim 3, wherein the cap member includes a part which is contacted toone of the cylinder or the frame, and to the inner stator, at the sametime.
 7. The apparatus according to claim 1, the cap member itself is aspring base for supporting the inner resonance spring elastically.